Pathological examination revealed a low prevalence of mild abnormalities among Hp-negative participants; in contrast, Hp-positive participants had a high prevalence of moderate-severe active and chronic gastritis; the prevalence of atrophic gastritis was 43% among Hp-positive participants and 0 among Hp-negative participants, while the prevalence of intestinal metaplasia was 17% among Hp-positive participants and 5% among Hp-negative participants. This evidence concerns the gene HP and chronic atrophic gastritis.